Constant speed drive for automobile generators and the like



pt. 30, 1952 T. w; HOR N- 2,612,249 7 CONSTANT SPEED DRIVE FOR AUTOMOBILE Y v NERATO S AND KE GE R THE LI Filed June 14. i948 2 SHEETS-SHEET 1 ISnnentor TH RMANW. HORN attorneys Sept. 30, 1952 HORN v CONSTANT SPEED DRIVE FOR AUTOMOBILE GENERATORS AND THE LIKE Filed June'14, 1948 'Zmventor THURMAN IM H RN #fim Gtto rnegs Patented Sept. 30, 1952 CONSTANT SPEED DRIVE FOR AUTOMOBILE GENERATORS AND LIKE Thurman W. Horn, Anniston,-Ala., assignor to Cabometer, Inc., a corporation of Alabama Application June 14, 1948, Serial No. 32,764

My present invention relates to 'apparatus for driving the generators of automobiles and the like at a substantial constant speed, whereby the generator delivers substantially its maximum current throughout the entire speed range of the automobile engine, thus to permit the operation of high load electrical devices such as radios and the like from the battery of the automobile.

It is an object of my invention to provide 4 Claims. (Cl. 192-104) apparatus of the character designated in which the generator is driven from the engine through a friction clutch having associated therewith springs and centrifugally actuated release devices, cooperating to maintain the speed of the generator substantially constant, regardless of the speed of the engine.

Another object is to provide a friction drive of the character designated in which heat generated by the slippage between the elements thereof is effectively dissipated by the construction and arrangement of the parts of the device, and by locating the apparatus in the air stream of the usual cooling fan for the engine. I r

Further objects are to provide a deviceof the character designated which shall be simple of construction and may be installed on existing automobiles without changing the engine or generator; in which the friction elements'have long trouble free life; which shall be free of objectionable noises whenin operation: and which in operation in no Way changes or disturbs the normal functioning of the generator current control devices usually associatedwith automotive generator systems.

In the art to which my invention relates, it has heretofore been proposed to drive a generator through an over drive mechanism, thereby to increase the speed and hence the output of the generator when the engine is idling. All such mechanisms'with which I am familiar have been equipped with means to completely disengage the generator from the engine when the latter attains a predetermined speed. In prior apparatus, therefore, the generator has been rotated either at a given relatively high speed or has been disengaged from the engine. My-apparatus differs from that heretofore proposed in that it permits the generator to be driven at a constant speed regardless of the engine speed.

Apparatus illustrating the features of my invention-is shown in thea'ccom'panying drawings, forming a part of this application,- in which:

Fig. 1 is a somewhat diagrammatic front elevational view showing my improved device in 2 place on a generator and driven from the crank shaft of the engine;

Fig. 2 is an exploded view of the pulley and clutch portions of my improved apparatus;

Fig. 3 is an exploded view of the supporting bracket and spindle on which the parts shown in Fig. 2 are mounted and supported;

Fig. 4 is a side elevational view of the assembled device, av portion of the bracket being broken away;

Fig; 5 is a detail sectional view partly broken away showing the device assembled;

Fig; 6 is a detail'sectional view taken along line VI.-VI of Fig. 4; I

Fig.v 'lfis a detailsectional view taken along line VII-VII of Fig. 4; and,

Fig. 8 is a detail sectional view drawn to an enlarged scale and taken along line VIII-V111 of Fig. 7. i

Referring now to the drawings for a better understanding of my invention and more particularly to Fig. 1 thereof, I illustrate my improvedapparatus in association with the crank shaft ID of an engine, not shown, and having a pulley H thereon. Disposed above the pulley H is the" usual fan 12 for delivering cooling air to the engine, and carrying a pulley l3. To one side of the crank shaft in, and mounted on the engine in any suitable manner, is ,a generator 14 having a pulley l6 on'the end' of the armature shaft 11.

Mounted on top of the generator I4 is a pedestal 18. The pedestal has a semicircular lower end IQ for fitting about the body of the generator, and is held thereto by means of semicircular clamps 2 l, bolts 22, and nuts 23 therefor.

The pedestal is provided at its upper end with a bore 24. Disposed to fit slidably and rotatably in the bore 24 is the rear end 26 of a mounting shaft 21. The forward portion 28 of the shaft 21 is eccentrically offset with respect to the rear end 26, and forms a spindle for supporting the rotating parts of my improved apparatus as will be presently described. The end 26 is held nonrotatably within the bore by means of a set screw 29. The forward end of the spindle 28 is threaded as indicated at 3|, and is provided with a small crossopening 32.

Mounted on the spindle 28 in side by side relation and for independent rotation relative to each other, are pulleys 33 and 34, provided with ball bearings 36 and 31, respectively. The pulleys are held in axiall'y spaced relation by means of fianged collars 38 and 39 and by an inter-' mediate sleeve 4|. The collars and sleeve engage the ends of the inner races of the ball 3 bearings 36 and 31, collar 39 abutting against the shoulder 42 forming the point of connection between the portions 26 and 28 of the shaft 21. A castellated nut 43, screwed onto the threaded end 3| engages the face of the collar 38, thus to hold the parts on the shaft. The nut may be locked by means of the usual cotter pin 44 passing through the nut and the opening 32 in the end of the spindle 28. The pulleys 33 and 34 thus are mounted on the spindle 28 for rotation relative to each other, and are held fixedly in axially spaced relation.

The clutch mechanism for coupling the pulleys 33 and 34 together to effect constant speed rotation of the pulley 34 will now'be described. Adjacent the inner face of the pulley 33 is a disc 46, preferably formed of a materialhavinga hardness of the order of iron, although itmay be formed of other material. The disc 46 carries on its side adjacent the pulley 33 a pair of protuberances '41'di'sposed to fitin sockets formed in theside of the pulley 33, to hold the pulley and plate' iefagainst relative rotation.

Disposed adjacent the face of the pulley 34 is a disc '49which maybe 'formed of material similar to the disc 46. The disc 49 carries a pair of rearwardly extending pins and 52, which project slid'ably'through openings 53 and '54 in the'pulley 34. The projecting ends of the pins are threaded as indicated at 56 and 51. In'ter'posed betweenthe discs 46 and 49 is a disc of friction material 58; such for instance as asbestos, woven belting orth'e like.

The inner face of the pulley is provided with a plurality of recesses 59jforming sockets for receiving a plurality of compression springs 6|. The opposite ends of the springs'Bl bear against the rear face of the disc "49'andbias the same toward the discof friction. material 58, thus forming a 'clutch to frictionally lock the. pulleys 33 and34' together. It is tobe notedthat'Iprovide a number of'spri'n'gs '61, whereby the engaging pressure of the -'clisc.49 toward the disc 58 is appliedevenly over the entire area .of the disc, thus preventing spot'wea'r of the discs.

The projecting ends of thepins5l and 52.pass loosely through 'openingsi-B2-and53 providedin the ends of 'apair: or elongated weights s4 and B6. The weights arepividtally mountedonthe pin's5l and 52, and are held in place thereon by means of jam nuts 61 and- 68. On the .faceof each weight adjacent the.pulley. 34-I provide a pair of hemisphericalsockets.69. "The sockets are disposed on either side-of theflopenings 62 and 63 through which i pass the. pins .5 l and 1 52. On the adj'acent'face of the. pulley 34 Iprovidefsimilar hemispherical sockets TH likewise located on either side of the openingsin the pulley through which pass thepinsKSI .andi52. Disposeddn the sockets "are steelsballs .12. The balls and sockets thus provide. cam -means. for effecting rearward movement of the disc 49, against theforce -of the springs 56] .whenever the-weights -'64 and 66 pivot aboutthepins, in themanner to-be described.

'The driving. arrangement for transmitting rotary motion from'thecrankshaftl 0. tc-the arma ture shaft I1 is completed --by the provisionof belts andI'l3 passing respectively over the pulleys l I, l'3fandl33, and the pulleys 1-6 and 34.

From the. foregoinglthe method of constructing and operating my improvedapparatusmay now be readily understood. -As-is :knowmautomobilegenerators usually are connected directly to 'theengine by a beltpassing over. pulley ll,

pulley I3, and pulley l6 carried on the armature shaft [1. In those instances wherein the automobile is driven for a majority of the time at idling speeds, it is found that the battery generally becomes exhausted of current because the generator does not produce suflicient amperage at idling speed of the engine to-maintain the battery charged. With my -improved'apparatus assembled and installed in the manner shown and described, the pulley 33 is driven through the belt 10 at a rate of speed dependent solely upon "the ratio of the diameter of the pulleys II and 33. By suitably adjusting the nuts 61 and 68 on the pins 51 and 52, the force of springs 6| urging the discs of the clutch together may be determined. The engaging pressure of the clutch elements may thus be regulated by a simple adjustment of the nuts, and when thus adjusted pulley 33 drives pulley 34, through the clutch. When thespeed of .pulley -34 exceeds the speed at which the .nuts '61. and '68 ar set to permit slippage of the .clutch, the free end of the weights 64 and-simoveoutwardly due to'centrifugal force. Thisaction causesthefweights vto ride upwardly on .the balls 12, pulling the pins 5| and 52Yfarther through the pulley 34, and hence moving disc 49 slightly away from the friction disc 58, against the force of springs 6i. This permits the pulley 33 to slip with respect to the pulley '34, therebyv maintaining thespeed of the pulley-34 ata predetermined rate. I have found that lthe.centrif ugally actuated weights tend to remain such .a :position that the pulley 34 is driven ata constant speed throughout the range of speedoflthe engine abovethe rangepredeterminedby the setting of the=nuts. 6' l and 68.

In view :of the fact that generators usuallyzinstalled .on automobiles I generate. their maximum current at a speed considerably higher than engine'idling speed, I preferably make the pulley 34 of larger diameter than the pulley 33, thereby to obtain an overdrive of thegenerator at idling speed of the engine. Likewise, 1 preferably make the pulleys 33 and of a material. havingahigh rate-cf heat dissipation, such for instance as aluminum, in .order to assure =long life .forthe discs. '46,."49 and 58; As-before-stated, I preferably. mount thepulleys so thatthey receive-cooling air from the fan-12, thus further aidingain preventing overheating of vthe device. By, loosening set screw '29, the-shaft 2.1 may be 'rotated therebyto' tightenthe belts 1 0 and 13. I

From the foregoing, it will be apparent .thatI have devised an improvedapparatus rorv driving a generator from the engme ofautomobile ior thelike, which-issimpleof operation and'in which the. generator is driven at :a substantially constantspee'd, throughout a1l-ranges of speed i of the. engine .from idling-to ..full :throttle position. In .actual operation, I have .-found that I adevice constructed in accordance --wi-th my invention. is satmfactory-in-every wayrand that the same .is particularly-useful for installation on automobiles wherein increased chargingfcapacity for the battery is needed; suchrfor-instanca-ns in those cases wherein the.- automobile; is equipped with :.radio. I havefound-thatthe discpf-friction-mriteriaihas unusually long li-fe,-:.and.-it-wlll be; obvious item the; drawings that the 5 same mayv be i'rreplaced without undue 'diificulty; andx-withouttremov the 'devicefrom: the :generator. .It :is to the: especi-ally noted that: at-ino: time 'the generator entirely ;disconnected: from :the engine, but that on the." other--hand :thezsame operates within a range of speed as determined by a single adjustment of the nuts 61 and 68. g

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof and I desire,

therefore, that only such limitations shall be generator, a friction clutch interposed betweenthe pulleys, there being a plurality of recesses in the side of the pulley driving the generator adjacent said friction clutch, compression springs in said depressions biasing said friction clutch toward a position to lock said pulleys together, a pair of axially movable pins carried by one element of the clutch and limiting theclutch on gaging pressure exerted by the springs, and centrifugally actuated members carried by the pins and movable to a position to decrease the clutch engaging pressure when the speed of said pulleys reaches a predetermined value.

2. Apparatus as defined in claim 1 in which the centrifugally actuated members compris a pair of elongated weights, each of said pins passballs disposed in sockets in the adjacent faces of the weights and said other pulley and disposedupon rotation of the weights to draw the pins through said other pulley against the force of the springs.

4. In apparatus for driving a generator and the like from anv engine embodying a pulley driven from the engine and a pulley mounted alongside the first pulley and operatively connected to drive the generator, the improvements comprising a stationary shaft on which the pulleys aremounted for rotation and in axially fixed position relative to each other, a pair of clutch discs fitting about the shaft between the pulleys and slidable axially on the shaft, a disc of friction material surrounding the shaft and c interposed between the clutch discs, a pair of axially disposed pins carried by the clutch disc adjacent. the generator driving pulley and projectlng slidably through openings in said generator driving pulley there being a plurality of recesses in the side of said generator driving pulley facing the adjacent clutch disc, a plurality of compressionfsprings in said recesses bearing against the adjacent clutch disc,

threaded sections on the projecting ends of said pins, eccentrically mounted weights loosely surrounding the projecting ends of said pins, nuts I 'on the threaded ends of the pins holding said weights assembled thereon, and cam means between the nuts andthe adjacent face of the generator driving pulley efiective when the weights ing through one of the pulleys and through one end of said weights, and in which the ends of the pins carry nuts for regulating the clutch engaging pressure exerted by the compression springs.

pulley, a disc of friction material between said r metal discs, springs interposed between the second disc and its associated pulley and pressing the discs into frictional engagement, pins secured to the face of the second disc adjacent said other pulley and extending slidably therethrough, threaded sections on the outer ends of the pins, elongated weights disposed on the face of said other pulley opposite the second disc, said pins passing loosely through one end of each weight, adjusting nuts on the threaded ends of the pins for drawing the second disc toward said other pulley against the force of the springs, and steel 1 rotate on the pins to move the pins and-hence the clutch disc carried thereby toward thegenerator driving pulley. I

, 'II-IURMAN W; HORN.

vfile of this patent:

UNITED STATES PATENTS Number Name Date 453,033 Blount May 26,1891 456,392 Ballard July 21, 1891 462,028 Ballard Oct. 27, 1891 659,194 Baynes Oct. 2, 1900 1,167,850 Smith Jan. 11, 1916 1,198,633 Heins Sept. 19, 1916 1,284,192 Harris Nov. 15, 1918 1,555,370 Heidegger -Sept. 29, 1925 1,670,877 Bruckmann May 22, 1928 2,079,724 Van Ranst May 11, 1937 2,122,218 Sneed June 28, 1938 2,376,939 Ricart May 29, 1945 2,432,591, S-chuckers Dec. 16, 1947 FOREIGN PATENTS Number Country Date 497,611 France Dec. 11, 1919 551,985 Great Britain Mar. 18, 1943 Denmark 1 Feb. 25, 1946 

